Abstract: The central reaction in glycosciences is arguably glycosylation, the formation of the glycosidic bond that connects a sugar motif to another molecule. It can be performed enzymatically through the use of glycosyl transferases or chemically using glycosyl donors and acceptors. Surprisingly, while the enzymatic mechanism has gained a high level of knowledge and sophistication, some of the details of the chemical glycosylation mechanism are still poorly understood.1Both mechanisms probably involve transient glycosyl cations to some degree. Observation, characterisation and further exploitation of these key ionic species is challenging but could have a significant impact on glycosciences. Our recent contribution to this field will be presented.2